[Mesa-dev] [PATCH] etnaviv: keep track of buffer valid ranges

[Wladimir]

On Thu, Oct 19, 2017 at 11:52 AM, Christian Gmeiner
<christian.gmeiner at gmail.com> wrote:

>>> +   if ((usage & PIPE_TRANSFER_WRITE) &&
>>> +         prsc->target == PIPE_BUFFER &&
>>> +         !util_ranges_intersect(&rsc->valid_buffer_range,
>>> +                                box->x, box->x + box->width)) {
>>> +         /* We are trying to write to a previously uninitialized range. No need
>>> +          * to wait.
>>> +          */
>>
>> This unbalances the cpu_prep/fini in the map/unmap path. This isn't
>> allowed and the kernel will start to reject this in the near future.
>>
>
> Good to know that the kernel will reject this behauvior in the near future.

Seems a good idea nevertheless, and very welcome after rework, I've
seen some cases of excessive flushing coming from here.

Wladimir